The present invention relates to a photoelectric conversion element, a photosensor, and an imaging device.
A conventional photosensor is an element in which a photodiode (PD) is formed in a semiconductor substrate such as silicon (Si), and as a solid-state imaging device, a planar solid-state imaging device, in which PDs are two-dimensionally arranged and signal charge generated by each PD is read out by a circuit, is widely used.
In order to obtain a color solid-state imaging device, a structure in which color filters that transmit light of a specific wavelength are arranged in a light incident surface of the planar solid-state imaging device is generally used. Currently, a single plate solid-state imaging device, in which color filters that transmit blue (B) light, green (G) light, and red (R) light are regularly arranged on each of the two-dimensionally arranged PDs, is well known and is widely used in a digital camera and the like.
Meanwhile, a technique is known in which, for the purpose of suppressing dark currents or the like, an electron blocking layer is introduced into a photoelectric conversion element used in a photosensor or a solid-state imaging device (for example, JP 2012-94660 A).